Hey guys, new to this forum so please be patient. I got the car a couple of months ago, after sitting 8 years. So far lots of labor, car does run. At least is has, but not lately, lol. I found a major rust hole in a steel line in the back of the motor area. It is the line that "T"s off the air rail system disappearing behind the engine. So two part question, where does the line go, and what is its function? The car has ran, then started loosing rpm, and eventually quit.
Thanks
Phil

 

Not really sure myself, haven't gotten that far! Depending on where you live, and if you have to meet emissions standards, MANY people have eliminated this system. Others will chime in.

 

Here's an illustration of the system....well, sort of. It show the RH air rail only, but the left is the same. You can see how the two sides join together at the back of the engine and also see the check valve.

Air Injection Pipes-5.3 Litre - Parts For XJS from (V)139052 to (V)179736 | Jaguar Classic Parts UK

Yes, many owner remove the system and lug the holes...if local regulations don't require emission system testing/inspection.

The system injects fresh air into the exhaust ports when the engine is cold. At x-temperature a divertor valve opens and the air pump output vents to atmosphere.

Cheers
DD

 

the back of the air rail. goes under to the right hang side. to the air pump.
I got rid of all of that on mine. after 30 years it essentially doesn't work anyway all clogged up. and whenit was new it's only on for 45 seconds to heat up the cats.
I'd rip it all out. idk how Texas is with emissions.

 

Thanks guys. In my area of Texas they don't check emissions, so what I am hearing is to not worry too much about the hole in the pipe directly under the check valve. Just wanted to make sure it didn't have anything to do with the running/not running situation. Still learning site, so I am sure I'll post to the wrong section quite soon.
Thanks
Phil

 

Item #13 in the above linked illustration? A hole there won't hurt anything, as long as the check valve isn't leaking, as that's the air *supply* to the air rails.

A hole on the other side of the check valve wouldn't be good, though.




Cheers
DD

 

We were all newbies at some point, don't feel bad! If you check the posts, you will find out how other members deleted this system.
Welcome to your new resource!

 

I removed mine when I did the last service on the motor, its frees up so much more room in the V so you can get to the important things like plugs and distributor and the injectors. I simply just tapped the little steel plates that hold pipes in place used a sealing bolt and bolted them back in. When you get a chance also remove the pump and its plumbing from the front of the motor, relocate the alternator to where the air pump is and relocate the AC pump to where the alternator was and you have just freed up so much of your motor you wont think its the same one, you have also allowed air to pass through the V and reduce the dreaded cooking of your internals. Or you can remove the pump and use an idler pulley in its place.
I am yet to do this on the motor in the car, but it will be done on the replacement motor I am building for it. Still there is lots of information out there on Air pump removal and utilising the area.
As far as emissions go I do remember reading that somebody else had removed the air pump and if the motor was running correct it didn't make difference to the results. I think it may have been on Jaglovers, but not 100% sure.
Good luck

 

Katoh, could you share some pics of your engine with these modifications?

Thanks.

 

Yeah Sure!

These pics are of the motor in the car, I have a second motor that I'm going to build, it has a 5 speed manual box on it and I'm going to load it up with some goodies, biggest problem is time, I won't get a chance to play with that one for another year or so, so I've done some half hearted jobs on the motor in the car just to keep it going and have a weekend cruiser.
modA_zps7149a22d.jpg?t=1400567708

first mod you can see I've removed the trumpets from the air filter box's gives the motor so much more air and a nice growl to suit. You may notice some wiring on top of the plenium
that's a new injector harness.

modB_zps4104cb1e.jpg?t=1400567579
You can see the nice shiny new bolt there, that little piece of steel is what held the air pipes in place, simply remove the pipes and tap that hole where the pipe went through to fit a bolt. I used 1/4" UNF tap and 1/4 x 1/2" bolts. There are little rubber seals in those holes under the steel plate, leave them there and the excess bolt threads into them nicely sealing it again.

modC_zpsa5bc12a3.jpg?t=1400567586
Front end look without the extra useless plumbing, you can see already how much more open it is becoming, imagine if that AC pump was gone from there. I wont move it on this motor, no point but the other one its gone. Yes also the hood is missing, its having pressed louvres put into the the back of it. I've seen this done on another XJS and it looked factory but most of all its going to let all that darn hot air out. I will post pics on another thread for the hood.
If you want to see who this all looks with the air pump gone and AC pump and alternator move then follow this link.XJ-SC Modifications
Hope this helps.

 

The link that Katoh posted has extensive relocations of its entire accessory drive.

I'd like to approach this in baby steps - replace air pump with alternator (dump smog pump and move alt to its location). So the factory alt and factory AC compressor would be driven off the same belt. I suspect this is going to require fabrication of a new mounting bracket, maybe the belt tightening bolt as well (note bent and relocated bolt in pic). Does anyone have a drawing or dimensions for this?

Perhaps stage 2 can involve AC comp relocation to clear up the vee, that would require fabbing new AC lines etc

To the OP, sorry for the thread hijack

 

Warlock
There are lots of different ways to attack the same problem, as in the pic this bloke simple bent a piece of aluminium and went his way, the trick to it is to use as many as the on board tension's as you can. Use the air pump one to support the Alternator and just simply measure and weld two bits bit 5mm plate steel to make a holding bracket, line up with existing holes and drill and fit. I don't think anyone has dimensions on bracket sizes, they are mainly done on the fly.
What you really want to achieve in my opinion is to move the alternator to where the air pump is now, then use one of the newer AC pumps and place it where the alternator was. "BINGO" now you have deleted the air pump and moved the AC pump out of the V. Then to really tidy up the front end remove the clutch fan and the small thermo and use two decent size thermo fans and a cowl from say an AU Ford Falcon and your down to 2 belts and a very empty front motor.
hope this helps.